1. Field of the Invention
The present invention relates to a multi-output power supply for preventing power imbalances between multiple outputs during an initial driving operation.
2. Description of the Related Art
In general, a power supply has been widely used in commercially-used electronic devices in addition to devices such as personal computers, and domestic appliances such as air conditioners, stereo systems, and audio-visual devices, in the past.
A power supply may supply a plurality of output power sources according to an electronic product to which the power supply is applied.
A general multi-output power supply converts input power into alternating current (AC) powers through a transformer and then rectifies the AC powers to output a plurality of direct current (DC) powers.
However, in the general multi-output power supply, when a voltage level of a single DC power among a plurality of DC powers is changed by the transformer, the remaining DC powers are affected by the change in the voltage level, and thus, cross-regulation may not be maintained.
To this end, a buck chopper circuit is used in an output terminal of the multi-output power supply.
A buck chopper circuit may include a switch, a diode for free wheeling, and a filter.
Thus, the general multi-power supply primarily converts power and then reconverts the power using the buck chopper circuit, thereby being reduced in power conversion efficiency. In addition, the number of components may be increased due to the presence of the buck chopper circuit configured as described above, thereby increasing manufacturing costs.
To overcome this problem, the Cited Reference below discloses a multi-output power supply for controlling switching of an output terminal thereof in synchronization with a switching signal of a power converting terminal.
The multi-output power supply performs a soft switching operation to stably supply power during an initial operation. In this case, power imbalances between multiple output powers may occur due to an imbalance in a switching duty ratio.